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NVIDIA: Llama 3.1 Nemotron Ultra 253B v1

nvidia/llama-3.1-nemotron-ultra-253b-v1:free

Model weights

Llama-3.1-Nemotron-Ultra-253B-v1 is a large language model (LLM) optimized for advanced reasoning, human-interactive chat, retrieval-augmented generation (RAG), and tool-calling tasks. Derived from Meta’s Llama-3.1-405B-Instruct, it has been significantly customized using Neural Architecture Search (NAS), resulting in enhanced efficiency, reduced memory usage, and improved inference latency. The model supports a context length of up to 128K tokens and can operate efficiently on an 8x NVIDIA H100 node.

Note: you must include detailed thinking on in the system prompt to enable reasoning. Please see Usage Recommendations(opens in new tab) for more.

Modalities

Price

Free

Context

131K

Released

Apr 8, 2025

Knowledge Cutoff

Mar 2024

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Activity

Token volume and request traffic to this model over time.

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Frequently asked questions

Llama-3.1-Nemotron-Ultra-253B-v1 is a large language model (LLM) optimized for advanced reasoning, human-interactive chat, retrieval-augmented generation (RAG), and tool-calling tasks. Derived from Meta’s Llama-3.1-405B-Instruct, it has been significantly customized using Neural Architecture Search (NAS), resulting in enhanced efficiency, reduced memory usage, and improved inference latency.

Yes. The pricing shown on this page for Llama 3.1 Nemotron Ultra 253B v1 is zero, so you are not charged for prompt or completion tokens. Free endpoints are rate limited — see the rate limit docs.

Llama 3.1 Nemotron Ultra 253B v1 has a 131,072 token context window.

Nemotron 3.5 Lightning, Nemotron 3.5 Content Safety (free), Nemotron 3 Ultra and 3 more are other text models from Nvidia.

Llama 3.1 Nemotron Ultra 253B v1 was released on April 8, 2025. Its knowledge cutoff is March 31, 2024.